I have a 2005 Hyundai Elantra with 106, 789 miles on it. I switched to 5w-20/30w full synthrtic motor oil about a year ago, car seens to run much better. Two months ago had a new timing belt, water pump and pulley put in by authorized mechanic shop. Now about a week and a half ago I checked the oil and it was about a 1 1/2 qt down, filled, checked yesterday about 1/2 qt down. It does not blow any snoke out exhaust, checked all over see no leaks, nothing under car on ground. I was thinking about putting in 5w-30w full synthetic motor oil High Mileage oil in, heard it can seal rings, etc. Also will pull spark plugs to see if there is [censored] all over them, Also there is no oil mixed in with the Anti Freeze, or Anti Freeze in the oil, the radiator cap is clean underneath, and just reversed flushed collant system few day ago, looked just fine (do it every two years). Anybody have any deas, suggestions. Thanks a lot. Fred J. [email protected]